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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 25 Configuring Network Securi t y w it h ACLs Examples for Compiling ACLs

Displaying Access Groups

Note Th is fea ture is available o nly i f your sw itch i s r unn ing the EI .
You use the ip acce ss-group in terface co nfiguration c omman d to apply ACLs to a Layer 3 in terface.
When IP is enabled on an interface, you can use the show ip interface interface-id privileged EXEC
command to view the input and output access lists on the interface, as well as other interface
characteristics. If IP is not enabled on the interface, the access lists are not shown.
This exampl e shows how to view all ac cess groups co nfigured for VL AN 1 and for Gigab it Eth ernet
interface 0/2:
Switch# show ip interface vlan 1
GigabitEthernet0/2 is up, line protocol is down
Internet address is 10.20.30.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is permit Any
Inbound access list is 13
<information truncated>
Switch# show ip interface fastethernet0/9
FastEthernet0/9 is down, line protocol is down
Inbound access list is ip1
The only way to ensure that you can view all configured access groups under all circumstances is to use
the show running-config privileged EXEC command. To display th e ACL configurati on of a single
interface, use the show running-config interface interface-id command.
This exam ple sh ows how to displa y the ACL con figuratio n of G igabi t E the rnet i n terface 0 /1:
Switch# show running-config interface gigabitethernet0/1
Building configuration...
Current configuration :112 bytes
!
interface GigabitEthernet0/1
ip access-group 11 in
snmp trap link-status
no cdp enable
end!

Examples for Co mpiling ACLs

For detailed information about compiling ACLs, refer to the Security C onfiguration G uide and t he IP
Services chapter of the Cisco IOS IP a nd IP Rout ing Configuration G uid e for I OS R ele ase 12.1.
Figure 25-2 shows a sm all netwo rked of f ice with a stack of switc hes that are connected to a Cisco r outer .
A host is connected to the network through the Internet using a WAN link.